The red-headed cardinal beetle is a predator; it lies in wait for small flying insects, sometimes for hours, in the upper layers of the tall vegetation near water. If you look you will find it around the edge of the reserve’s ponds.
In the UK, three species of beetle go by the name of cardinal. There is the black headed cardinal beetle (Pyrochroa coccinea), the scarce cardinal beetle (Schizotus pectinicornis) and this one above, the red headed or common cardinal beetle (Pyrochroa serraticornis) but only the last of them has ever been identified in the reserve.
Header image by Gail Hampshire (CC BY 2.0) wikimedia.com